Hone and abrasive element therefor



Jan. 16, 1962 M. J. GROSS 3,016,660

HONE AND ABRASIVE ELEMENT THEREFOR Filed July 31, 1959 malordce QJ-GVOJJwr%, JM OJH M 3,016,660 HUNE AND ABRASIVE ELEMENT THEREFQR Maurice .1.Gross, Rockford, 111., assignor to Barnes Drill (lot. Rockford, 11]., acorporation of Illinois Filed July 31, 1959, See. No. 830,910 2 Claims.(Cl. 51-1845) This invention relates to a tool for honing a cylindricalsurface and comprising a rotary slotted body carrying a plurality ofabrasive sticks each comprising an elongated bar of bonded abrasiveknown as a stick together with a carrier through which the stick issupported laterally or backed in the tool body by material adapted towear away with the working face of the stick during the honingoperation.

The primary object of the invention is to provide a novel carrierconstruction which is simple and inexpensive to manufacture, whichprovides the desired backing for the abrasive stick While avoidingfouling of the working face of the stick, which avoids cocking of thestick and rubbing thereof against a wall of the body slot and which maybe fastened easily to the stick and to a supporting member in the honingtool.

Another object is to provide a novel carrier which can be formed easilyand inexpensively from a single piece of sheet material such as aluminumand fastened conveniently to the honing stick to provide a backing forthe trailing side of the stone, and a depending flange for convenientattachment to the supporting member in the honing tool, while at thesame time maintaining a desired spacing between the leading face of thestick and the opposed wall of the body slot.

A more detailed object is to form the carrier as a one piece stamping ofZ shape having two flanges projecting in opposite directions fromopposite edges of a crosspiece and respectively backing the trailingside of the stick and properly spacing the leading side from the opposedwall of the body slot.

Other objects and advantages of the invention will become apparent fromthe following detailed description taken in connection with theaccompanying drawings, in which FIGURE 1 is a fragmentary sectional viewtaken along the line 11 of FIG. 2 of a tool equipped with a honingelement embodying the novel features of the present invention.

FIG. 2 is a fragmentary sectional view taken along the line 2-2 of FIG.1.

FIG. 3 is a perspective view of the honing element.

FIG. 4 is a fragmentary perspective View of the carrier of the honingelement.

As illustrated in the drawing, the improved honing element is especiallyadapted for use in a rotary honing tool of the multiple stick typecomprising a hollow generally cylindrical body secured to the end of arotary spindle 11 and having a plurality of parallel sided longitudinalslots 12. The latter are angularly spaced around and open outwardly fromthe body, and each receives a honing element 13 comprising an abrasivestick 14 and a carrier or holder 15 therefor. Herein, each stick is anelongated rectangular block of bonded abrasive somewhat shorter andnarrower than the body slot.

Rigidly backing each honing element 13 within each slot 12 is anelongated bar 16 of rectangular cross section having inwardly projectingfollowers 17 which engage conical cams 18 fixed on a push rod 18a. Thelatter is slidable axially back and forth through the hollow drivespindle 11 and, when it is shifted in one direction, herein downwardlyas viewed in FIG. 1, the honing elements are shifted outwardly toproject the outer faces 19 of the abrasive sticks 14 beyond theperiphery of the body 10 and against the wall of a work bore 29. Whenthe rod is retracted upwardly, the honing elements are permitted toshift inwardly for collapse of the bone, this being effected herein bythe usual garter springs 21 which encircle and engage the outer sides ofprojections 22 on the ends of the follower bars. To avoid axial shiftingrelative to the body, the bars fit closely between end walls 23 of thebody slots 12 (FIG, 1).

In accordance with the present invention, the carrier 15 for each honingelement 13 is formed as an elongated member of Z-shaped cross sectionwith two parallel flanges 24 and 26 projecting in opposite directionsfrom opposite edges of a crosspiece 27 and spaced apart a distance atleast equal to and preferably somewhat greater than the width of theabrasive stick. One flange 26 lies against one side of the abrasivestick 14 to separate the strip from the trailing side wall 25 of thebody slot 12 and provide a backing for the trailing edge of the workingface 19. The crosspiece underlies and is secured to the bottom of thestick and cooperates with the other or mounting flange 24- to define arecess for receiving the follower bar 16, this flange being fasteneddetachably to the bar for movement of the element with the bar.

The backing flange 26 extends throughout the length of the abrasivestick 14 and is wide enough to cover all of the trailing side of thestick within the body slot 12 when the honing element is first put intoservice use.

Preferably, as shown in FIGS. 2 and 3, the flange is made slightlynarrower than the usual width of the sticks to accommodate variations inthe widths of different sticks while insuring that the flange does notproject beyond the working face 19. The material selected for the flangeis one which wears away with the stick but does not tend to load or foulthe working face, that is, clog the pores therein. Due to the Z shape ofthe carrier, adhesive securing the latter and the stick together may belocated on the bottom of the stick so that the backing flange isdetached from the trailing side of the stick. Thus, there is no adhesivewhich, during wearing away of the stick and the flange, is liable toload the working face and reduce the cutting elficiency of the abrasiveparticles.

The width of the crosspiece 27 is correlated with the thickness of theflanges 24 and 26 so that the latter substantially lie against oppositeside walls of the body slot 12 when the honing element 13 is assembledon the fol lower bar 16 within the slot. At the same time, the flange 24is spaced from the flange 26 a distance at least equal to the width ofthe abrasive stick and in any event such that the outer face of theflange 24 is disposed in or outwardly beyond the exposed side face ofthe abrasive stick which face, in the final assembly, opposes theleading wall of the body slot 12.

Preferably, the abrasive stick 14 is secured over the full length of itsbottom to the upper side of the crosspiece 27 so that, in the event ofthe cracking or breaking of the stick into several pieces as oftenoccurs in service, the individual pieces will all remain secured to thecarrier 15 thus permitting continued use of the stick. A suitableadhesive is ordinary Du Pont cement applied as a film to the bottom ofthe stick and covering the crosspiece. The cffectiveness of the adhesiveis increased by forming spaced holes 30 in the crosspiece, some of theadhesive flowing into these holes to form lugs which interlock with thecrosspiece when the adhesive hardens.

To assist in holding the abrasive stick 14 and the carrier 15 assembledas the unitary honing element 13 or to assist in the selection ofabrasive sticks of proper width, lugs 31 bent up from the crosspiece 27or the mounting flange 24 lie substantially in the plane of the latterand cooperate with the crosspiece and the backing flange 26 to form achannel-like seat for the stick. Preferably, the lugs are struck out ofthe crosspiece so as to form the holes 30 for the adhesive in the sameoperation. In the Patented Jan. 16, 1962 event that the stick isnarrower than the channel between the lugs and the backing flange, thestick is positioned against the flange and the space between the stickand the lugs is filled with adhesive.

With the lugs 31 thus disposed in the plane of the flange 24 and lyingagainst the leading and exposed face of the abrasive stick 13, it willbe apparent that this face will, in the final assembly of the honingtool shown in FIG. 2, be separated by a gap 33 from the opposed guidewall of the body slot 12 which wall lies in flat face to face contactwith the outer surface of the carrier flange 24. By such positivespacing, the abrasive is held out of contact with this slot wall notonly at the outset but throughout the service life of the stick in spiteof the tendency of the honing element to cock or tilt in its mountingrelative to the slot under the reaction torque exerted by the work onthe working face 19. As a result, the guide walls of the slot remainsmooth and undamaged throughout the life of the tool body.

To secure the honing element assembly 13 detachably to the follower bar16 when the latter is seated in the recess defined by the crosspiece 27and the mounting flange 24, at least one and preferably two fasteningdevices 28 are formed on the latter for interengagement with fasteningdevices 29 on the follower bar. In this instance, each of the devices 29comprises a cylindrical pin fitting snugly in a hole 32 in the followerbar and projecting outwardly from the leading side thereof into a recessor hole whose defining edges constitute the other device 28 on themounting flange 24. The holes 28 in the carrier 15 aline with the holes32 in the bar in the assembled relation of the two, the holes extendingall the way across the bar in this instance.

By employing two pins spaced along the follower bars, the carrier 15 foreach abrasive stick is located securely to its supporting follower andheld positively against radial tilting. In addition, the pins 29 areutilized to perform the additional function of transmitting directly tothe hone body the end thrust exerted on the working faces of theabrasive sticks during engagement of the latter with the work to behoned. This is accomplished by fitting each pin 29 snugly on thefollower bar 16 and making the pin long enough to project its oppositeends beyond opposite sides of the bar and into peripheral grooves 35 cutin the exterior of the hone body iii and disposed in the axial planes inwhich the carrier holes 28 and the pins 29 are disposed when thecarriers are attached to their follower bars 16 and the latter areseated in the body slots 12 between the ends 23 of these slots. Thegrooves 30 are only slightly wider than the diameter of the pins 29 butare deep enough to accommodate the full range of radial adjustment ofthe carriers 15 incident to wearing away of the abrasive sticks inservice use.

By virtue of its Z shape, the carrier 15 may be formed easily andinexpensively by simple stamping operations in which the backing flangeis bent up and the mounting flange is bent down from an integral flatsheet after the cuts for the lugs 31 and the hole 28 have been made. Amaterial found to be especially suited for such operations and capableof wearing away with the abrasive stick without loading the working face19 is so-called half-hard aluminum sheeting having a thickness ofapproximately .025 of an inch. Another material found to be satisfactoryfor the carrier is a thermosetting phenolic type resin material such asInsurok T640 made by the Richard son Company.

To install the improved honing element 13 in the hone body 10, thefollower bar 16 is assembled on the element by seating the bar in therecess between the crosspiece 27 and the mounting flange 24 andprojecting the pins 29 through the alined holes 28 and 32 in the carrierand follower bar leaving opposite ends of the pins projectingsubstantially equal distances from opposite sides of the assembly asshown in FIG. 2. Then, each assembly is pressed edgewise into a slot 12of the body, the projecting ends of the pins 29 entering the grooves 35.After similar assemblies have been inserted in all of the body slotswith their followers 16 seated against the earns 18, the garter springs21 are shifted over the follower projections 22 thus completing theassembly of the tool.

This application is a continuation-in-part of my copending applicationSer. No. 689,890, filed October 14, 1957, now abandoned.

I claim as my invention:

1. A honing element having, in combination, a carrier comprising a sheetof material of Z-shaped cross-section having a backing flange and asecond flange paralleling each other and projecting in oppositedirections from opposite sides of an intermediate crosspiece, saidcrosspiece and said second flange cooperating to define a bottom recessfor receiving a supporting bar, means formed on said second flange forfastening the same de tachably to the supporting bar, a lug upstandingfrom said carrier at the junction of said second flange and crosspieceand paralleling said backing flange so as to cooperate with the latterand the crosspiece in defining a channel-like seat, and a rigidgenerally rectangular abrasive member including a stick of bondedabrasive and secured in said seat with the bottom supported by saidcrosspiece and one side face lying against said backing flange, theopposite side face of said member being exposed and located in a planewhich parallels and is disposed between said backing flange and said lugwhereby the latter acts as a spacer for maintaining said exposed faceout of contact with a flat guide wall lying against said second flange.

2. In a honing tool, the combination of, a rotary body having a radiallyopening slot defined by parallel walls. an elongated carrier of Z-shapedcross-section having a backing flange and a second flange parallelingeach other and projecting in opposite directions from opposite sideedges of an intermediate crosspiece normal to said flanges, said backingflange and said crosspiece defining a seat, a rigid generallyrectangular abrasive member including a stick of bonded abrasive andsecured insaid seat with the bottom supported by said crosspiece and oneside face lying against said backing flange, the opposite side face ofthe member being exposed, a radially movable mounting bar in said slotunderlying said crosspiece and lying against said second flange tosupport said carrier and sustain the radial pressure on the radiallyexposed working face of said abrasive stick, means detachably securingsaid second flange to said bar, said abrasive member being narrower thansaid crosspiece so as to dispose the exposed side face of the memberwithin the plane of the outer face of said second flange and therebyprevent rubbing contact between said exposed face of the member and thewall of said slot engaged by said second flange.

References {Iited in the file of this patent UNITED STATES PATENTS1,800,213 Floss Apr. 14, 1931 2,102,093 Qingley Dec. 14, 1937 2,330,184Hause Sept. 21, 1943 2,612,010 Phillips Sept. 30, 1952 2,823,498Saunders Feb. 18, 1958

